Circular knitting machines have a multiplicity of moving parts, such as needles, sinkers, jacks, selectors, control cams, etc., that are necessary for knitting a fabric. These parts are mounted in compact spaces in close proximity to each other and since they operate at high speed, it is necessary to lubricate them by the application of oil thereto.
Since the knitted fabric is taken down inside the rotating cylinder and is flattened and wound on a take-up roll beneath the cylinder, oil stains on the knitted fabric is a too frequent problem, which significantly reduces or depreciates the value of the knitted fabric resulting in financial loss to the fabric manufacturer. Such oil leaks occur by oil running down the cylinder and along the gear ring and dripping therefrom onto the fabric roll and by oil collecting on the cam ring and running along the upper surface of the bed supporting the cam ring and dripping onto the fabric inside the machine through holes for wiring and piping.
Attempts at solving this problem have been proposed previously, but have not been successful or have created additional problems or have effected adversely the operation of the knitting machine. One example of a proposed attempt is the provision of an oil pan inside the knitting machine below the gear ring and bed. Because space is very scarce in a circular knitting machine, the space occupied by such an oil pan means that the ease of operation of the knitting machine is sacrificed. Also, it is very difficult to remove oil from the pan and to remove the pan for cleaning. Consequently, this proposal has not been found to be a realistic solution to the problem.
A very common practice is to attempt to have a worker wipe off the oil as it leaks and before it drips onto the fabric. It can readily be appreciated that timing in such an endeavor is critical and results have been poor.